In an interview with the Big Think, Harvard professor Louis Menand explains “the trick of writing for places like the New York Review of Books or The New Yorker“:

The general way to think about your audience is to think about somebody who’s like yourself, but in a completely different discipline. So I generally think of a biologist, or professor of biology. So if I’m writing about T. S. Eliot, this is probably someone who’s heard of T. S. Eliot, may have read some T. S. Eliot in college, but doesn’t know a whole lot more about T. S. Eliot, because they’re busy doing more important things with their brains, but they might be interested in something that I have to say about T. S. Eliot.

Also:

If you write for The New Yorker, you always get people critiquing your grammar, you can count on it. So, because a lot of New Yorker readers are kind of, you know, amateur grammarians.

And speaking more generally on the changing position of the critic: “Print is no longer king,” Menand says. “No duh.”